Automotive airbag systems include an airbag module mounted within a housing that is concealed beneath a surface of the vehicle interior. In particular, passenger airbag systems may include a chute defined by the housing and extending within the dashboard of the associated vehicle. The chute may be concealed beneath a surface of the dashboard or instrument panel substrate. In such an arrangement, the passenger airbag chute door (which may also be referred to as the “roof” of the chute) extends over an opening of the airbag assembly and is supported by a portion of the housing from the airbag canister, which may include a wall of the chute. The chute door may be weakened to facilitate tearing when a threshold amount of energy is applied to the underside thereof during activation of the airbag. The adjacent portion of the dashboard or instrument panel substrate may include a pre-weakened tear line that ruptures upon airbag deployment, allowing the airbag to deploy within the chute, out of the opening thereof, and from out of the dashboard.
In applications where the chute is covered by a portion of the instrument panel, multiple layers of material may extend over the door of the chute and other areas outward thereof, such material typically being bonded with both the door and the surrounding portions of the instrument panel support structure. Such layers may include the visible, outer layer of the instrument panel as well as intermediate layers, which may include foam or the like (used for “soft touch” instrument panel structures). Some variations of these covered arrangements may be “seamless” structures in which the outermost instrument panel layer is not pre-weakened along any particular predetermined tear seam. Depending on the type of material used for the outer layer of the instrument panel, the force necessary for airbag deployment to tear the un-weakened material may be appreciably greater than pre-weakened structures or in arrangements employing weaker materials. In an example, leather instrument panels may require a particularly high level of deployment force. Accordingly, further advances in airbag chutes and related structures are desired.